- ALLEN RAINE - see PUDDICOMBE, ANNE ADALISA
- ALLEN, EVAN OWEN (1805 - 1852), writer
- ALLEN, JAMES (1802 - 1897), dean of S. Davids and antiquary
- ALLEN, JOHN ROMILLY (1847 - 1907), archaeologist
- ALLEN, LANCELOT BAUGH (1774 - 1845), lawyer - see ALLEN, JOHN ROMILLY
- ALLEN, ROBERT (1847 - 1927), Baptist minister
- ALLGOOD family
- ALLTUD EIFION - see JONES, ROBERT ISAAC
- ALLTUD GLYN MAELOR - see JONES, JOHN ROBERT
- ALMER family Almer, Pant Iocyn,
- ALMOR, Almer, Pant Iocyn - see ALMER
- ALUN - see BLACKWELL, JOHN
- ALYS MALLT - see WILLIAMS, ALICE MATILDA LANGLAND
- ALYS MEIRION - see WILLIAMS, ALICE HELENA ALEXANDRA
- AMANWY - see GRIFFITHS, DAVID REES
- AMBROSE, WILLIAM (Emrys; 1813 - 1873), Independent minister, poet, and littérateur
- AMBROSE, WILLIAM ROBERT (1832 - 1878), Baptist minister and antiquary
- AMBROSIUS AURELIANUS (fl. ( c. 475)), British leader
- AMNON - see JONES, REES
- ANARAWD ap GRUFFYDD (d. 1143), prince
- ANARAWD ap RHODRI (d. 916), prince
- ANDREAS O FÔN - see BRERETON, ANDREW JONES
- ANDREWS, JOSHUA (c.1708 - 1793), Baptist minister
- ANDRONICUS - see JONES, JOHN WILLIAM
- ANEIRIN (fl. second half of the 6th century), poet
- ANELLYDD - see THOMAS, ARTHUR SIMON
- ANEURIN FARDD - see JONES, ANEURIN
- ANGHARAD (d. 1162)
- ANGHARAD, ferch MORGAN ap MEREDUDD (1293 or 1299) - see IFOR HAEL
- ANGLESEY, 7th Marquess of - see PAGET, GEORGE CHARLES HENRY VICTOR
- ANGLESEY, Marquess of - see PAGET
- ANIAN (d. 1306?), bishop of Bangor
- ANIAN (d. 1266), bishop of St Asaph
- ANIAN (d. 1293), bishop of St Asaph
- ANN of SWANSEA - see HATTON, ANN JULIA
- ANNE TEMPLE - see HUGHES, HYWEL STANFORD
- ANTHONY, DAVID BRYNMOR (1886 - 1966), school teacher and academic administrator
- ANTHONY, GRIFFITH (1846 - 1897), musician
- ANTHONY, HENRY MARK (1817 - 1886), landscape painter
- ANTHONY, WILLIAM TREVOR (1912 - 1984), singer
- ANTHROPOS - see ROWLAND, ROBERT DAVID
- ANWYL family Park, Llanfrothen
- ANWYL, Sir EDWARD (1866 - 1914), Celtic scholar
- ANWYL, EDWARD (1786 - 1857), Wesleyan minister
- ANWYL, JOHN BODVAN (Bodfan; 1875 - 1949), minister (Congl.), lexicographer, and author
- ANWYL, LEWIS (1705? - 1776), cleric and author
- ANWYL, THOMAS (fl. late 16th or early 17th century), poet
- AP CALEDFRYN - see WILLIAMS, WILLIAM
- AP CEREDIGION - see LEWIS, DAVID
- AP DYFRDWY - see LLOYD, OWEN MORGAN